This section provides background information related to the present disclosure which is not necessarily prior art.
Multi-cell electrochemical devices, also referred to as battery cell stacks or multi-cell battery modules, can be used for a variety of applications, including powering various electronic devices, for vehicle propulsion, etc. While battery designs such as alkaline, voltaic pile, and lead-acid batteries are used in various household and industrial applications, evolving battery types such as nickel cadmium (NiCd), nickel-metal hydride (Ni-MH), lithium ion, and lithium ion polymer batteries display particular utility in emerging electric and hybrid gas/electric vehicle propulsion applications, due in part to increases in energy densities. Such batteries can be selectively rechargeable, for example, either as plug-in style batteries or onboard during a regenerative braking event, depending on the particular configuration of a vehicle.
In certain battery cells, electrode and separator sheets of adjacent cells can be laminated onto each other in order to provide a variety of cell stacking geometries and other cell configurations, whether aboard a vehicle or for other non-vehicular applications. For example, battery cells can be positioned adjacent one another, and their respective conductive terminals or cell tabs can be connected together in a particular manner suitable for completing the electrical circuit. In some cases, multiple tabs of the same or similar materials can be joined to another material, such as an interconnecting member, using ultrasonic welding methods. These methods, however, can result in variations in weld quality as portions of the ultrasonic tooling (e.g., horn and anvil) wear during use. Such wear also affects welding performance and presents an ongoing tooling expense. Moreover, the geometry and position of the interconnecting member relative to the cell tabs has to accommodate the ultrasonic welding apparatus, thereby limiting aspects of the multi-cell device design and configuration.